Data from monitors installed by Heathrow confirms A380s are noisier than supposedly “noisier” planes they are replacing

Date added: January 18, 2017

The Teddington Action Group (TAG) has been adamant for several years that they are experiencing excessive noise from A380s overhead, especially take-offs towards the east, and especially late evening and night. TAG has now found that these supposedly “quieter aircraft” are in fact noisier than the planes they are replacing. The data from noise monitors, installed by Heathrow, at the National Physical Laboratory and Strawberry Hill House. The data, (Mar-Sept 2016), shows that “quieter” A380s departing directly over the monitors achieved an average noise of 76.5 decibels, compared to an average of 73.8 dB for “noisier” Boeing 747s. Moreover, TAG has discovered that the CAA and DfT have used “double counting” to manipulate elements of the very same data, so to to create an artificially low noise average for the A380s. Noise has been measured by two monitors and somehow this has been computed together to given an allegedly lower noise reading. TAG says: “The DfT argues that Heathrow expansion is made possible by a new generation of quieter aircraft. It’s one thing to learn that this platitude is as fallacious as overflown residents have long known. But quite another to learn that data has been self evidently manipulated by the authorities to shore up the fallacy.”
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Noisier Actually…

Data from monitors installed by Heathrow confirms that A380s are noisier than the supposedly “noisier” planes they are replacing (contrary to DfT claims)

18..1.2017 (TAG – Teddington Action Group – press release)

Corroborating the experience of overflown residents, research conducted by Teddington Action Group (TAG) has established that the new generation of supposedly “quieter aircraft” are in fact noisier than the planes they are replacing.

The research relies on data from noise monitors, installed by Heathrow, at the National Physical Laboratory and Strawberry Hill House, to the South West of London.

The data, gathered between March to September 2016, shows that “quieter” A380s departing directly over the monitors achieved an average noise of 76.5 decibels, compared to an average of 73.8 dB for “noisier” Boeing 747s.

Moreover, TAG has discovered that the CAA and DfT have used “double counting” to manipulate elements of the very same data, so to to create an artificially low noise average for the A380s.

For example, on 2 April 2016, noise generated by one A380 flight, is presented as if it had been made by two separate flights, with the data it produced at each of the monitors (which are 1.5km apart), being computed together to reduce the average. (see Notes 2)

The extent of this manipulation is confirmed by the CAA’s acknowledgement that it relied upon 1,368 noise events to compute their average decibel level for departing A380s; because readings were only taken for 986 identifiable flights, during the period.

This is tantamount to an admission that a minimum of 383 flights must have been double counted, so computing a lower average. (see Notes 3)

Speaking for TAG, Neil Spurrier said:

“We now know that the Airbus A380 is noisier than all the planes it is replacing, including the Boeing 747-400 and Airbus A340.

“The DfT argues that Heathrow expansion is made possible by a new generation of quieter aircraft. It’s one thing to learn that this platitude is as fallacious as overflown residents have long known. But quite another to learn that data has been self evidently manipulated by the authorities to shore up the fallacy.”

“It is misleading the public about Heathrow expansion. For not only is the large, heavy, low flying A380 noisier to residents on the ground, but they are used for long haul destinations, so depart early in the morning and late at night. And are exactly the type of plane that will massively increase as a proportion of the fleet if Heathrow expands”.

(1) The DfT has already acknowledged that the A380s are louder on arrivals than the “noisier” (!) planes they are replacing.

(2) On the 2nd April 2016 making 79.6 decibels. It was also picked up by the National Physical Laboratory at 63.8 decibels – namely an under-reading of some 15.8 decibels due to the distance. However, the CAA and the DfT are using this reduced reading to compare the A380 as quieter. The second reading is set up as a “combination” which is then “quieter” than the 747s picked up by the same monitor.

(3) During the period March to September 2016, the CAA recorded:

– 690 A380s going over Strawberry Hill House making an average of 76.5 dB each

– 125 Boeing 747s going over Strawberry Hill House making an average of 76.5 dB

– 38 A380s going over the National Physical Laboratory making an average of 72.1 dB

– 133 Boeing 747s going over the National Physical Laboratory making an average of 73.8 dB

986 TOTAL PLANES or “NOISE EVENTS” (A380s and 747s)

In fact, with the double counting the CAA recorded 1,368 noise events – 382 extra.

Each of the planes had a standard instrument departure programmed into it following one of the two particular noise preferential routes out of Heathrow

Of the 986 planes, 690 were A380s at least as loud or louder than 258 747s. Just 38 A380s were quieter. That is to say that 94.78% of A380s were as loud as or louder than 747s. Apart from the 38 A380s no plane was recorded as louder than the A380 on the overhead measurements. The CAA and DfT created two further “ghost routes” by recording some (but not all) of the planes at the other noise monitor over which the planes did not fly so that:

– Of the 690 planes over Strawberry Hill House, 213 were recorded at 63 dB by the NPL Noise Monitor

– Of the 125 747s going over Strawberry Hill House 59 were recorded at 66 dB by the NPL Noise Monitor

– Of the 38 A380s going over the National Physical Laboratory 24 were recorded at 65 dB by the SHH Noise Monitor

– Of the 133 Boeing 747s going over the National Physical Laboratory 83 were recorded at 68 dB by the SHH Noise Monitor

By these “Ghost routes” and double counting of selected planes at lower noise levels the A380 suddenly becomes, from being noisier, quieter on “3 out of 4 SID and Noise Monitor combinations”

(4) How or why the noisier of two planes overhead becomes the quieter of the two as recorded by a monitor one kilometre away is open to speculation. It could be that some of the A380s are at the opposite end of the cone increasing the distance from the neighbouring monitor. It could be that the A380s are flying lower thus concentrating the noise upon the ground beneath it, thus creating extra noise and suffering for the people in its wake. The DfT have said that “if a noise event for a particular departure is registered at a nearby noise monitor but not at another monitor located further away it simply means that the aircraft was too quiet to register a valid noise event at the more distant monitor”. That cannot be the case here since the louder planes are being excluded from the duplication process. In the first three weeks of the CAA’s data and 100 hundred A380s recorded, 63 were double counted and 47 were not double counted – i.e. those 47 were recorded only by the Noise Monitor that they overflew. However, of those 47 A380s, no less than 20 were louder than the average of 76.5 dB recorded. Therefore, some of the loudest planes are not being double counted thus reducing the recorded noise in the ghost route. Whatever the reason for not double counting, it is not going to be that the planes were too quiet to register a valid noise event.

Even though the A380 is as noisy or noisier than the 747, it is classified in a lower noise category entitling it to fly into the night. Indeed, Heathrow have altered the nightly flight paths allowing more to fly to the east over densely populated areas citing quieter aircraft saying:

“The rules and incentives in place mean airlines are increasingly using their quietest planes on early morning routes. Average noise per take-off and landing has already fallen by 20%. And with more airlines introducing the significantly quieter A380 to their fleets, we expect this trend to continue”.

Campaigners against a third runway at Heathrow believe residents in west London are suffering more noise from a new breed of aircraft that the Government promised would be quieter.

Residents claim there has been “insufferable” misery for thousands living close to the flight path since double-decker Airbus A380 planes began replacing Boeing 747s.

The claim, disputed by the Department for Transport, is the latest row in which official promises about environmental standards have been challenged by campaigners against expansion at London’s premier airport.

Neil Spurrier, chair of Teddington Action Group, said: “Teddington was relatively unaffected by aircraft noise but now the area gets 17 hours per day of almost insufferable noise for about a third of the time, when the wind blows from the east.”

The group’s claim comes after it analysed data from two Civil Aviation Authority noise monitors based on top of Strawberry Hill House in Twickenham and the National Physical Laboratory at Teddington over a four-month period.

The group said the measurements show that for every month, the A380 was noisier than the 747s and accused the Government of suppressing noise averages by inconsistently recording jets on either one or both monitors. However, the Government said the action group’s claims were incorrect.

A DfT spokesman said: “There has been no double counting or attempt to falsify results on noise pollution at Heathrow. There are two noise monitors a mile apart and only some flights will be picked up by both as they detect flights over a certain volume for a minimum time.”

The DfT admitted the A380 is louder on arrival than predecessor planes, but is quieter overall.